This study describes the sexual beginning, the behavioral and affective factors associated in adolescents of the School Antonio Ávila. The used approach was of quantitative and descriptive type. 243 students constituted the sample; of which 75 belong to the first, 115 to the second one, and 51 to the baccalaureate third one.
For the information compilation, the questionnaire was used "Identification of Problematic" that was applied in the institution. The results inform that the age mediated in that the first sexual meetings appear he is 14 years old. The factors that have motivated the adolescents by the beginning of the sexual intercourse are the love in the women and the curiosity in the males. The polled students belong in the same proportion to nuclear families and monoparentales, this variable and the consumption of alcohol do not influence in the beginning of the sexual intercourse. For the most part, the adolescents know on contraceptive methods and the infections of sexual transmission, and inform that they have not been infected by one of these illnesses.